It makes me cringe just watching it. I wonder though if you damaged your tire by a nail or whatnot, how would you know you're riding on a damaged tire? Are they saying that getting a nail in the tire, that you just ignore it?

You just cant take any chances with tyres when younger i met the tarmac up close because the tyres failed as time went on i got better informed on type and life of a tyre
But dont think id want to trust a gel in tyre to keep me alive
Different on 4 wheels

I wonder how they would work if the nail or screw that punctured the tread were to left in the tire and then rode at road speed for several hours. That is the way it happens in the real world. Things just don't go in and then immediatly come out. I wonder how well the gel seals when a long nail stays in the tire and it rolls for 60 miles. I suspect that would not fair as well.